Range

Range is a measurement used to determine how far an autoattack or ability can reach. Riot tends to describe that distance in a vague measurement of "units". It shares the scale of "units" with movement speed, so one point translates to one game distance unit traveled. Note that autoattack range is measured differently to ability range. Given a source unit's hitbox and a target unit's hitbox, range is calculated as follows: autoattack range from edge to edge; targeted skill range from center to center; skillshot range from edge to edge; and the range of self-centered area of effects are from the edge of the source (the larger champions don't benefit less from auras than smaller champions). The difference is approximately 100 (i.e. 550 autoattack range is roughly 650 casting range)[1][2][3]

Each champion begins the game with a particular base autoattack range. This can vary from 125 to 250 for melee units and 300 to 650 for ranged units. As of 7.11, the highest autoattack range is 750 held by Kindred with 32 marks, surpassing the 669 range of level 18 Tristana'sDraw a Bead at 20 marks (675). Caitlyn as the highest autoattack range at level 1 with 650, surpassed by Tristana at level 16 with 655 autoattack range.

Size Model Modifiers

Ranges calculated from the edge of a champion's hitbox will see an increase or decrease in reach based on the champion's current size. Note that a change in range due to the champion's size is only relative to the champion's center and is not an explicitly mentioned effect (i.e. the champion's attack range stat will not increase).

Champions

Innate

Thus far, Zac is the only champion with the innate quality of constantly modifying his size.